In order to prevent traffic accidents, an advanced emergency braking system (AEBS) is increasingly mounted on vehicles. Further, automatic driving of vehicles has been developed actively, and the automatic driving is classified into a plurality of levels including a level that one or more of acceleration, braking, and steering are automatically performed, through a level that all of the acceleration, braking, and steering are performed completely automatically. In the AEBS, an automatic driving control device is a device that determines how to brake a vehicle and how to accelerate, brake and steer the vehicle in automatic driving and performs control. In a vehicle into which such an automatic driving control device is mounted, when an deceleration speed based on an operation of a brake pedal is larger than a predetermined value, stop lamp lighting control to be made by the brake pedal is prioritized over lamp flashing control during an automatic brake operation (for example, see PTL 1).